Display device, transmitting terminal, receiving terminal and wireless communication system

ABSTRACT

A display device may include: an acquisition unit acquiring transmitting terminal identification information that is identification information of a transmitting terminal transmitting image data by wireless communication, and receiving terminal identification information that is identification information of a receiving terminal receiving the image data by wireless communication; and an information display unit displaying the transmitting terminal identification information and the receiving terminal identification information.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. application Ser. No. 15/077,501filed on Mar. 22, 2016, which is a divisional application of U.S.application Ser. No. 14/612,452 filed on Feb. 3, 2015, which is acontinuation application of U.S. application Ser. No. 13/869,598 filedon Apr. 24, 2013, which is a continuation of PCT Patent Application No.PCT/JP2011/066701, filed Jul. 22, 2011, whose priority is claimed onJapanese Patent Application No. 2010-246615, filed on Nov. 2, 2010, theentire content of which are hereby incorporated by reference in theirentirety.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to a display device, a transmittingterminal, a receiving terminal, and a wireless communication system.

Description of the Related Art

Conventional art is known in which, in a display means of an apparatusthat communicates wirelessly, a list is displayed of identificationinformation of other apparatuses capable of communicating with the localapparatus (refer to, for example, Japanese Unexamined PatentApplication, First Publication No. 2001-197150). Also, a wirelesscommunication system used in an operating room or the like is known,which is constituted by a plurality of imaging apparatuses and aplurality of display apparatuses, and in which switching is done, asnecessary, of the combination of the wireless communication between theimaging apparatuses and the display apparatuses.

SUMMARY

The present invention provides a display device, a transmittingterminal, a receiving terminal, and a wireless communication system thatfacilitates an understanding of the wireless communication connectionrelationship.

According to a first aspect of the present invention, a display devicemay include: an acquisition unit acquiring transmitting terminalidentification information that is identification information of atransmitting terminal transmitting image data by wireless communication,and receiving terminal identification information that is identificationinformation of a receiving terminal receiving the image data by wirelesscommunication; and an information display unit displaying thetransmitting terminal identification information and the receivingterminal identification information.

According to a second aspect of the present invention, in the displaydevice according to the first aspect, the information display unit mayfurther display information indicating that the image data istransmitted from the transmitting terminal to the receiving terminal.

According to a third aspect of the present invention, the display deviceaccording to claim 1 may further include: a connection unit thatconnects the transmitting terminal or the receiving terminal in order totransmit or receive information.

According to a fourth aspect of the present invention, the transmittingterminal may include: the display device according to the first aspect.

According to a fifth aspect of the present invention, the receivingterminal may include: the display device according to the first aspect.

According to a sixth aspect of the present invention, in the receivingdevice according to the fifth aspect may include: an image data displayunit that displays the image data.

According to a seventh aspect of the present invention, a wirelesscommunication system having a plurality of communication devices thatwirelessly communicates image data may include: a plurality ofidentification information display devices that visually display theidentification information established for each individual communicationdevice; and a communication status display device that displays a flowof the image data between the communication devices. The identificationinformation may be uniquely established at the time the communicationdevices join the network.

According to an eighth aspect of the present invention, in the wirelesscommunication system according to the seventh aspect, the identificationinformation display devices may be connected to or mounted in aone-to-one relationship on the communication devices.

According to a ninth aspect of the present invention, the wirelesscommunication system according to the seventh aspect or the eighthaspect may further include: a connection switching device that displaysthe identification information and the flow of the image data betweenthe communication devices on the same screen, and that also controlsswitching of the flow of the image data according to an instruction.

According to a tenth aspect of the present invention, a wirelesscommunication system, in which a terminal that wirelessly transmitsimage data is referred to as a transmitting terminal, a terminal thatwirelessly receives image data is referred to as a receiving terminal,and a device that instructs to switch a wireless communicationconnection between the transmitting terminal and the receiving terminalis referred to as a connection switching device, the wirelesscommunication system having a plurality of the transmitting terminals, aplurality of the receiving terminals, and at least one of the connectionswitching device, may include: a first display device connected by cableto the transmitting terminal to display transmitting terminalidentification information that is identification information of thetransmitting terminal; and a second display device connected by cable tothe receiving terminal to display receiving terminal identificationinformation that is identification information of the receivingterminal. The connection switching device may display the transmittingterminal identification information displayed on the first displaydevice, the receiving terminal identification information displayed onthe second display device, and information indicating that the imagedata is wirelessly transmitted from the transmitting terminal to thereceiving terminal.

According to an eleventh aspect of the present invention, in thewireless communication system according to the tenth aspect, theconnection switching device may wirelessly receive the transmittingterminal identification information from the transmitting terminal andthe receiving terminal identification information from the receivingterminal, respectively.

According to a twelfth aspect of the present invention, the wirelesscommunication system according to the tenth aspect may further include:a third display device that is connected by cable to the receivingterminal to display information indicating that the transmittingterminal identification information and the image data are wirelesslytransmitted from the transmitting terminal corresponding to thetransmitting terminal identification information.

According to a thirteenth aspect of the present invention, the wirelesscommunication system according to the tenth aspect or the twelfth aspectmay further include: a fourth display device that is connected by cableto the transmitting terminal to display information indicating that thereceiving terminal identification information and the image data arewirelessly transmitted to the receiving terminal corresponding to thereceiving terminal identification information.

According to a fourteenth aspect of the present invention, in thewireless communication system according to the tenth aspect, thereceiving terminal may have an image data display unit that displays theimage data.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a simplified drawing illustrating the constitution of awireless communication system in accordance with the first preferredembodiment of the present invention;

FIG. 2 is a block diagram indicating the constitution of the videocameras and the identification information display devices in accordancewith the first preferred embodiment of the present invention;

FIG. 3 is a block diagram illustrating the constitution of the displays,the communication status display devices, and the identificationinformation display devices in accordance with the first preferredembodiment of the present invention;

FIG. 4 is a simplified table illustrating the data structure of theidentification information control table in accordance with the firstpreferred embodiment of the present invention;

FIG. 5 is a simplified table illustrating the data structure of thecommunication status information control table in accordance with thefirst preferred embodiment of the present invention;

FIG. 6 is a flowchart illustrating the processing protocol of theinitial processing for the cameras in accordance with the firstpreferred embodiment of the present invention;

FIG. 7 is a flowchart illustrating the processing protocol of the mainprocessing of the video camera in accordance with the first preferredembodiment of the present invention;

FIG. 8 is a flowchart illustrating the processing protocol of theterminal exploring processing and table updating processing of the videocameras in accordance with the first preferred embodiment of the presentinvention;

FIG. 9 is a simplified drawing illustrating the constitution of awireless communication system in accordance with the second preferredembodiment of the present invention;

FIG. 10 is a block diagram illustrating the constitution of thecontroller in accordance with the second preferred embodiment of thepresent invention;

FIG. 11 is a simplified drawing illustrating the identificationinformation display screen in accordance with the second preferredembodiment of the present invention;

FIG. 12A is a simplified drawing illustrating connection informationdisplay screens in accordance with the second preferred embodiment ofthe present invention;

FIG. 12B is a simplified drawing illustrating connection informationdisplay screens in accordance with the second preferred embodiment ofthe present invention;

FIG. 13 is a flowchart illustrating the processing protocol forcontroller communication processing by the controller in accordance withthe second preferred embodiment of the present invention;

FIG. 14 is a flowchart illustrating the processing protocol of theterminal exploring processing and the table updating processing by thecontroller in accordance with the second preferred embodiment of thepresent invention;

FIG. 15 is a flowchart illustrating the processing protocol of the videocameras in accordance with the second preferred embodiment of thepresent invention; and

FIG. 16 is a flowchart illustrating the processing protocol of thedisplays in accordance with the second preferred embodiment of thepresent invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS First Preferred Embodiment

A first preferred embodiment of the present invention will be describedbelow, with references made to the drawings. FIG. 1 is a simplifieddrawing illustrating the constitution of a wireless communication systemin accordance with the first preferred embodiment of the presentinvention. In the illustrated example, a wireless communication system100 is constituted by two video cameras 1 and 3 that have the functionof wirelessly transmitting captured image data, and two displays 2 and 4that receive and display the image data transmitted from the videocameras 1 and 3. In the first preferred embodiment, the displays 2 and 4are pre-established as the transmission destinations of image data bythe video cameras 1 and 3. In the illustrated example, the video camera1 has the display 2 as its transmitting destination of image data, andthe video camera 3 has the display 4 as its transmitting destination ofimage data. As a result, the display 2 displays the image captured bythe video camera 1, and the display 4 displays the image captured by thevideo camera 3.

An identification information display device 5 that displays the deviceidentification information of the local device is mounted on the videocamera 1. The device identification information is information thatuniquely identifies of each device. The device identificationinformation is determined by the video cameras 1 and 3 that are in the“parent” status, which will be described later. The method forestablishing the device identification information will be describedlater. In the illustrated example, because the device identificationinformation of the video camera 1 is C1, the device information displaydevice 5 displays C1. An identification information display device 8 ismounted on the video camera 3. In the illustrated example, because thedevice identification information of the video camera 3 is C2, theidentification information display device 8 displays C2.

A communication status display device 6 and an identificationinformation display device 7 that display device identificationinformation of communication destination device and communication statusinformation including the communication status with the communicationdestination device are mounted on the display 2. In the illustratedexample, the communication destination device of the display 2 is thevideo camera 1 and, because the display 2 and the video camera 1 arecommunicating, the communication status display device 6 displays C1,which is the device identification information of the communicationdestination video camera 1, and a right-direction arrow, which isinformation indicating that communication with the communicationdestination video camera 1 is in progress. Because the deviceidentification information of the display 2 is D1, the identificationinformation display device 7 displays D1.

A communication status display device 9 and an identificationinformation display device 10 are mounted on the display 4. In theillustrated example, the communication destination of the display 4 isthe video camera 3 and, because the display 4 and the video camera 3 arecommunicating, the communication status display device 9 displays thedevice identification information C2 of the communication destinationvideo camera 3, and a right-direction arrow, which is informationindicating that communication with the communication destination camera3 is in progress. Because the device identification information of thedisplay 4 is D2, the identification information display device 7displays D2. The device identification information of the destinationdevice and the information indicating that communication with thecommunication destination device is in progress, which are displayed onthe communication status display devices 6 and 9, are collectively takento be the communication status information.

As described above, because the identification information displaydevices 5, 7, 8, and 10 display device identification information thatuniquely identifies the local devices, and the communication statusdisplay devices 6 and 9 display the device identification information ofthe communication destination devices of the displays 2 and 4 andcommunication status information indicating the communication statuswith the communication destination device, a user can easily verify in avisual manner the combinations of video cameras 1 and 3 and the displays2 and 4, which perform communication.

Also, in the illustrated example, although the video cameras 1 and 3 donot have the communication status display devices 6 and 9, the videocameras 1 and 3 may be provided with the communication status displaydevices 6 and 9, so that they display the device identificationinformation of the communication destination device and the status ofcommunication with the communication destination device.

Also, for example, a combination of the communication status displaydevices 6 and 9 and the identification information display devices 7 and10 corresponds to the display device of the present invention. Forexample, the communication status display devices 6 and 9 correspond tothe identification information display device and the communicationstatus display device of the present invention.

Next, the constitution of the video cameras 1 and 3 and theidentification information display devices 5 and 8 will be described.FIG. 2 is a block diagram indicating the constitution of the videocameras 1 and 3 and the identification information display devices 5 and8 in accordance with the first preferred embodiment of the presentinvention. In the illustrated example, the video cameras 1 and 3 have animaging unit 11, an image processing unit 12, a wireless communicationunit 13, an antenna 14, a control unit 15, and a storage unit 51. Theidentification information display devices 5 and 8 are mounted on thevideo cameras 1 and 3. The identification information display devices 5and 8 have a connection unit 60, an acquisition unit 61, and a displayunit 62.

The imaging unit 11 has an optical system, an image sensor (for example,a CCD (charge-coupled device) or CMOS (complementary metal oxidesemiconductor) sensor), and an A/D converter. The imaging unit 11captures a photographed object, and converts the optical image of thephotographed object to a digital signal. The image processing unit 12generates image data from the digital signal converted by the imagingunit 11, and performs image processing of the generated image data. Thewireless communication unit 13 performs high-frequency processing of theimage data that is image processed by the image processing unit 12, andinformation to be transmitted to another device, such as deviceidentification information and communication status information, whichwill be described later, and transmits these wirelessly via the antenna14. The wireless communication unit 13 also receives, via the antenna14, information that is wirelessly transmitted from another device. Thestorage unit 51 stores information required for the processing invarious parts of the video cameras 1 and 3.

The control unit 15, by controlling the various parts of the videocameras 1 and 3, controls the operation of data transmission. Thecontrol unit 15 also, by controlling the various parts of the videocameras 1 and 3, as necessary, performs display information creationoperation or display information receiving operation. The displayinformation creation operation is the operation of creating deviceidentification information to be displayed on the identificationinformation display devices 5, 7, 8 and 10 included in the communicationsystem 100 and communication status information to be displayed on thecommunication status display devices 6 and 9, and transmitting thegenerated communication status information to another device. Thedetails of the display information creation operation will be describedlater. The display information receiving operation is the operation ofreceiving device identification information and communication statusinformation transmitted from a device that performs a displayinformation creation operation.

In the first preferred embodiment, of the video cameras 1 and 3 includedin the communication system 100, only the video camera 1, 3 firststarting operation performs the display information creation operation,the remaining video camera 1, 3 and the display 2, 4 performing thedisplay information receiving operation. A device that performs thedisplay information creation operation will be called a “parent device,”and the status of becoming a parent device will be referred as theparent status. Also, a device that performs the display informationreceiving operation will be called a “child device,” and the status ofbecoming a child device will be referred to as the child status.

The connection unit 60 is connected to the video cameras 1 and 3 bycable in order to perform communication. The acquisition unit 61, usingby serial communication by the cable connected to the video cameras 1and 3 via the connection unit 60, acquires device identificationinformation from the control units 15 of the video cameras 1 and 3. Thedisplay unit 62 displays the device identification information acquiredby the acquisition unit 61. By this constitution, the identificationinformation display devices 5 and 8 can display the deviceidentification information of the video cameras 1 and 3. Because themethod for displaying the information by this constitution is publiclyknown, the description thereof will be omitted.

Although the identification information display devices 5 and 8 shown inFIG. 2 are constituted as being separate from the video cameras 1 and 3,they may be integrated as a part of the video cameras 1 and 3. In thiscase as well, communication between the control units 15 of the videocameras 1 and 3 and the identification information display devices 5 and8 is performed by cable serial communication.

Next, the constitution of the displays 2 and 4 will be described. FIG. 3is a block diagram illustrating the constitution of the displays 2 and4, the communication status display devices 6 and 9, and theidentification information display devices 7 and 10 in accordance withthe first preferred embodiment of the present invention. In theillustrated example, the displays 2 and 4 have an antenna 16, a wirelesscommunication unit 17, an image processing unit 18, an image displayunit 19 (image data display unit), a control unit 20, and a storage unit52. The communication status display devices 6 and 9 and theidentification information display devices 7 and 10 are mounted on thedisplays 2 and 4. The communication status display devices 6 and 9 havea connection unit 63, an acquisition unit 64, and a display unit 65(information display unit). The identification information displaydevices 7 and 10 have a connection unit 66, an acquisition unit 67, anda display unit 68 (information display unit).

The wireless communication unit 17 receives, via the antenna 16, theimage data, the device identification information, and the communicationstatus information, which are wirelessly transmitted. The imageprocessing unit 18 performs image processing of image data in order todisplay on the image display unit 19 an image based on the image datareceived by the wireless communication unit 17. The image display unit19 displays an image based on the image data that has beenimage-processed by the image processing unit 18. The control unit 20, bycontrolling the various parts of the displays 2 and 4, performs controlof the image data receiving operation, of the display informationreceiving operation, which is the operation of receiving deviceidentification information and communication status information, and ofthe display operation based on the received data. The storage unit 52stores information necessary for processing in the various parts of thedisplays 2 and 4.

The connection unit 63 is connected to the displays 2 and 4 by cable inorder to perform communication. The acquisition unit 64, using serialcommunication by the cable connected to the displays 2 and 4 via theconnection unit 63, acquires communication status information from thecontrol units 20 of the displays 2 and 4. The display unit 65 displaysthe communication status information acquired by the acquisition unit64. By this constitution, the communication status display devices 6 and9 can display the communication status information of the displays 2 and4. Because the method for displaying the information by thisconstitution is publicly known, the description thereof will be omitted.

The connection unit 66 is connected to the displays 2 and 4 by cable inorder to perform communication. The acquisition unit 67, using serialcommunication by the cable connected to the displays 2 and 4 via theconnection unit 66, acquires device identification information from thecontrol units 20 of the displays 2 and 4. The display unit 68 displaysthe device identification information acquired by the acquisition unit67. By this constitution, the identification information display devices7 and 10 can display the device identification information of thedisplays 2 and 4. Because the method for displays the information bythis constitution is publicly known, the description thereof will beomitted.

Although the communication status display devices 6 and 9 and theidentification information display devices 7 and 10 are constituted asbeing separate from the displays 2 and 4, they may be integrated as apart of the displays 2 and 4. In this case as well, communicationbetween the control units 20 of the displays 2 and 4, the communicationstatus display devices 6 and 9, and the identification informationdisplay devices 7 and 10 is performed by cable serial communication.

Next, the identification information control table that is stored by thestorage units 51 of the video cameras 1 and 3 that are in the parentstatus in the first preferred embodiment will be described. FIG. 4 is asimplified table illustrating the data structure of the identificationinformation control table in accordance with the first preferredembodiment of the present invention. The identification informationcontrol table includes data items for ID numbers, device identificationinformation, and power supply status, and the data of each of the dataitems are stored in association with one another for each line.

The data item ID number stores the ID numbers of devices included in thecommunication system 100. The ID numbers are uniquely assigned to eachdevice beforehand. In the first preferred embodiment, the ID number ofthe video camera 1 is 0001, the ID number of the video camera 3 is 0003,the ID number of the display 2 is 0002, and the ID number of the display4 is 0004.

The data item device identification information stores deviceidentification information that is established for the device identifiedby the ID number stored on the same line. The data item power supplystatus stores whether the power supply of the device that is identifiedby the ID number stored on the same line is on or off.

In the illustrated example, on line 101 the value stored in the dataitem ID number is 0001, the value stored in the data item deviceidentification information is C1, and the value stored in the data itempower supply status is on. This indicates that the identificationinformation of the device identified by the ID number 0001 is C1 andthat the power supply of the device uniquely identified by the deviceidentification information C1 is on (on status). The other lines are asillustrated.

Next, the communication status information control table stored by thestorage units 51 of the video cameras 1 and 3 that have gone into theparent status in the first preferred embodiment will be described. FIG.5 is a simplified table illustrating the data structure of thecommunication status information control table in accordance with thefirst preferred embodiment of the present invention. The communicationstatus information control table includes data items for transmittingdevice identification information, and receiving device identificationinformation, the data of each of the data items being stored inassociation with one another for each line.

The data item transmitting device identification information storesdevice identification information of a device transmitting image data toa device that is uniquely identified by the receiving deviceidentification information stored in the same line. The data itemreceiving device identification information stores the deviceidentification information of a device receiving image data from adevice that is uniquely identified by the transmitting deviceidentification information stored in the same line.

In the illustrated example, in line 201, the value stored in the dataitem transmitting device identification information is C1, and the valuestored in the data item receiving device identification information isD1. This indicates that the device that is the image data transmittingdestination for the device uniquely identified by the deviceidentification information C1 is the device uniquely identified by thedevice identification information D1. The other lines are asillustrated.

Next, the processing protocol for processing at the startup of the videocameras 1 and 3 (initial processing) will be described. FIG. 6 is aflowchart illustrating the processing protocol of the initial processingfor the cameras 1 and 3 in accordance with the first preferredembodiment of the present invention. In the first preferred embodiment,of the video cameras 1 and 3 included in the communication system 100,the video camera of the video cameras 1 and 3 that starts operatingfirst is in the parent status, and the video camera that operates thesecond time and thereafter is in the child status.

(Step 1401)

When the video cameras 1 and 3 are started up, the control unit 15begins the initial processing. After that, processing proceeds to stepS1402.

(Step 1402)

The control unit 15 performs parent device detection processing. Parentdevice detection processing judges whether or not there exists a videocamera 1, 3 in the parent state within the communication system 100. Ifthe control unit 15 judges that there is no video camera 1, 3 in theparent status within the communication system 100, processing proceedsto step S1403, but if the control unit 15 judges that there is a videocamera 1, 3 in the parent status within the communication system 100,processing proceeds to step S1404. In the first preferred embodiment,only a video camera 1, 3 that is in the parent status performs terminalexploring processing and table updating processing, to be describedlater, and transmits an exploring signal to each device in thecommunication system 100 at regular intervals. For this reason, if thewireless communication unit 13 does not receive an exploring signalwithin a prescribed amount of time, the control unit 15 judges thatthere is no video camera 1, 3 that is in the parent status, and if thewireless communication unit 13 receives an exploring signal within theprescribed amount of time, the control unit 15 judges that there is avideo camera 1, 3 in the parent status.

(Step S1403)

The control unit 15 performs parent device setting processing to makeits own device a parent device. After that, processing proceeds to stepS1405. The parent device setting processing is processing that sets thelocal device to be a parent device and initializes the identificationinformation control table and the communication status control table.Then, it establishes the identification information of the local device,causes the established device identification information, the localdevice ID number, and the local device power supply status inassociation with one another in the identification information controltable, and further performs processing that causes display of theestablished device identification information on the identificationinformation display devices 5 and 8.

As a method for setting the parent device, for example, the control unit15 causes the storage unit 51 to store parent device information. Also,the initialization of the identification information control table andthe communication status control table is processing that deletes theinformation stored in each table. Although various methods ofestablishing the device identification information can be envisioned, inthe first preferred embodiment this is established in the settingsequence of model name and device identification information. Forexample, the model name of the video camera 1, 3 is made C, and themodel name of the display 2, 4 is made D. The model name is made thefirst character of the device identification information. The characterfollowing the first character is a number that is the deviceidentification information setting sequence number among the same model.Specifically, of the displays 2 and 4 within the communication system100, if the device identification information for the display 2 isestablished first, the device identification information of the display2 would be D1. Also, of the displays 2 and 4 within the communicationsystem 100, if the device identification information for the display 4is established second, the device identification information of thedisplay 4 would be D2.

(Step S1404)

The control unit 15 performs child device setting processing that makesits own device a child device. After that, processing proceeds to stepS1405. The child device setting processing is processing that sets thelocal device to be a child device. As the method of setting the childdevice, for example, the control unit 15 causes the storage unit 51 tostore child device information.

(Step S1405)

The control unit 15 starts up the main processing. After that, theinitial processing is ended.

By executing the above-described initial processing, a video camera 1, 3can set whether the local device is a parent device or a child device.If the local device is a parent device, the identification informationcontrol table and the communication status control table areinitialized. Additionally, the device identification information of thelocal device is established, the established device identificationinformation, local device ID number, and local device power supplystatus are stored in the identification information control table inassociation with one another, and the established device identificationinformation is caused to be displayed on the identification informationdisplay device 5, 8.

Specifically, if the video camera 1 starts up first, after which thevideo camera 3 starts up, the video camera 1 sets itself as a parentdevice. Then, it establishes its identification information as C1,stores the established identification information C1, the local deviceID number 0001, and the local device power supply status of on in theidentification information control table in association with oneanother, and causes display of the established identificationinformation C1 on the identification information display device 5, 8.The video camera 3 sets itself as a child device.

Next, the processing protocol for the main processing of the videocamera 1, 3 will be described. FIG. 7 is a flowchart illustrating theprocessing protocol of the main processing of the video camera 1, 3 inaccordance with the first preferred embodiment of the present invention.The main processing is executed in the video camera 1, 3 until each ofthe device power supplies are set to off.

(Step S1506)

When the main processing starts up at the initial processing step S1405,the control unit 15 starts the main processing. After that, processingproceeds to step S1507.

(Step S1507)

The control unit 15 judges whether its device is a parent device or achild device (parent/child judgment). Then, if the control unit 15judges that its device is a parent device, processing proceeds to stepS1508, and if the control unit 15 judges that its device is a childdevice, processing proceeds to step S1509. As an example of parent/childjudgment, the control unit 15 reads out the parent or child informationthat has been caused to be stored in the storage unit 51 in the initialprocessing, judging that its device is a parent device if the read-outinformation is parent and that its device is a child device if theread-out information is child.

(Step S1508)

The control unit 15 executes terminal exploring processing and tableupdating processing. After that, processing proceeds to step S1510. Theterminal exploring processing and table updating processing will bedescribed later.

(Step S1509)

The control unit 15 executes the table receiving processing. The tablereceiving processing is processing that receives the local deviceidentification information and communication status information that istransmitted from the video camera 1, 3 that is in the parent status. Thecontrol unit 15 also causes the received device identificationinformation of the local device to be displayed on the identificationinformation display device 5, 8. After that, processing proceeds to stepS1510.

(Step S1510)

The control unit 15, based on the communication status informationreceived at step S1509, judges whether or not the display 2, 4pre-established as the communication destination display 2, 4 of thelocal device is operating. If the control unit 15 judges that the localdevice communication destination display 2, 4 is operating, processingproceeds to step S1511, and if the control unit 15 judges that the localdevice communication destination display 2, 4 is not operating,processing proceeds to step S1512.

(Step S1511)

The control unit 15 controls the wireless communication unit 13 so thatthe image data for one screen that has been captured by the imaging unit11 and image-processed by the image processing unit 12 is transmitted tothe display unit 2, 4. After that, processing returns to step S1507.

(Step S1512)

After a certain amount of waiting time, the control unit 15 returns tothe processing of step S1507.

Next, the processing protocol for the terminal exploring processing andtable updating processing of the video cameras 1 and 3 will bedescribed. FIG. 8 is a flowchart illustrating the processing protocol ofthe terminal exploring processing and table updating processing of thevideo cameras 1 and 3 in accordance with the first preferred embodimentof the present invention.

(Step S1601)

The control unit 15 starts the terminal exploring processing and thetable updating processing. After that, processing proceeds to stepS1602.

(Step S1602)

The control unit 15 controls the wireless communication unit 13 andtransmits an explorer signal (explorer packet) to each device includingwithin the communication system 100. After that, processing proceeds tostep S1603. Upon a device receiving the explorer signal, the devicetransmits to the video camera 1, 3 that has transmitted the explorersignal a response signal that includes an ID number that is a numberuniquely assigned to the local device beforehand.

(Step S1603)

The wireless communication unit 13, via the antenna 14, receives theresponse signal transmitted from the device to which the explorer signalhas been transmitted at step S1602. The control unit 15 counts thenumber of response signals received by the wireless communication unit13 as the number of unprocessed IDs. After that, processing proceeds tostep S1604.

(Step S1604)

If the number of unprocessed IDs is one or greater, the control unit 15judges that the there is an ID number among the ID numbers included inthe response signals for which the processing of step S1605 to stepS1607 has not been performed, and processing proceeds to step S1605. Ifthe number of unprocessed IDs is zero, the control unit 15 judges that,among the ID numbers included in the response signals, received at stepS1602, there are no ID numbers for which the processing of step S1605 toS1607 has not been performed, and processing proceeds to step S1608.

(Step 1605)

The control unit 15 selects one ID number for which the processing ofstep S1605 to step S1607 has not been performed and judges whether theselected ID number coincides with an ID number stored in theidentification information control table. The control unit 15 alsosubtracts 1 from the number of unprocessed ID numbers. If the controlunit 15 judges that the selected ID number coincides with an ID numberstored in the identification information control table, processingproceeds to step S1607, and if the control unit 15 judges that theselected ID number does not coincide with an ID number stored in theidentification information control table, processing proceeds to stepS1606.

(Step S1606)

The control unit 15 establishes the device identification information ofa device that is identified by the selected ID number at step S1605, andstores the ID number and the established identification information, inassociation with one another, in the identification information controltable. After that, processing proceeds to step S1607. The method ofestablishing the device identification information is the methoddescribed with regard to the parent device setting processing.

(Step S1607)

The control unit 15, of the power supply flags stored in theidentification information control table, sets the power supply flag ofthe ID number selected at step S1605 to on. After that, processingproceeds to step S1604.

(Step S1608)

The control unit 15 compares the ID numbers included in the responsesignals received at step S1603 with the ID numbers stored in theidentification information control table. The control unit 15 thendetects as a non-responding ID number an ID number that is not includedin the response signals, is stored in the identification informationcontrol table, and also has a power supply status flag that is on. Ifthe control unit 15 detects a non-responding ID number, processingproceeds to step S1609, and if the control unit 15 does not detect anon-responding ID number, processing proceeds to step S1610.

(Step S1609)

The control unit 15, of the power supply flags stored in the informationcontrol table, sets to off the power supply flag of the ID numberdetected as a non-responding ID number at step S1608 (performs powersupply status flag off-setting processing). After that, the terminalexploring processing and the table updating processing are ended, andprocessing proceeds to step S1610.

(Step S1610)

The control unit 15, of the power supply flags stored in the informationcontrol table, transmits the device identification information and thecommunication status information for each device to a device that isuniquely identified by an ID number of which the power supply flag ison. After that, the terminal exploring processing and table updatingprocessing are ended, and processing proceeds to step S1510 of the mainprocessing.

If a video camera 1, 3 becomes a parent device by the execution of theabove-described initial processing, main processing, terminal exploringprocessing, and table updating processing, it is possible to performdisplay information creation operation. This display informationcreation operation is operation that generates the identificationinformation and the communication status information of both the parentdevice and the child device included within the communication system100, and transmits the generated identification information andcommunication status information of the child device to each of thedevices that are child devices included within the communication system100. Also, if a video camera 1, 3 has become a child device, it canreceive its device identification information from the video camera 1, 3that has become a parent device, and can display the received deviceidentification information on the identification information displaydevice 5, 8 mounted thereon. Also, in both the case in which a videocamera 1, 3 has become a parent device and the case in which it becomesa child device, if the display 2, 4 that is its communicationdestination is currently operating, it can transmit captured image datato the display 2, 4.

Next, the operation of the displays 2 and 4 will be described. Thewireless communication unit 17 of a display 2, 4 receives deviceidentification information, communication status information, and imagedata transmitted from the video camera 1, 3, via the antenna 16. Then,if the wireless communication unit 17 has received device identificationinformation, the control unit 20 causes the received deviceidentification information to be displayed on the identificationinformation display device 7, 10. If the wireless communication unit 17has received communication status information, the control unit 20causes the received communication status information to be displayed onthe communication status display device 6, 9. If the wirelesscommunication unit 17 has received image data, the control unit 20causes the image processing unit 18 to image-process and display on theimage display device 19 the received image data. By doing this, thedisplay 2,4 can display the device identification information on theidentification information display device 7, 10. The display 2, 4 canalso display the communication status information on the communicationstatus display device 6, 9. The display 2, 4 can cause display of theimage data on the image display unit 19.

Next, the specific operation of the communication system 100 of thefirst preferred embodiment will be described.

Specific Example 1 of First Preferred Embodiment

The case in which, in the communication system 100, the power supply ofthe display 2 is on, the power supplies of the display 4 and the videocameras 1 and 3 are off, the power supply of the video camera 1 is on,and the power supplies of the video camera 3 and the display 4 areturned on next.

Specific Example 2 of First Preferred Embodiment

The case in which, in the communication system 100, the power supply ofthe video camera 1 is off, the power supplies of the video camera video3 and the displays 2 and 4 are sequentially set to on, and then thepower supply of the video camera 1 is set to on.

The above-noted two specific examples will be described.

Specific Example 1 of First Preferred Embodiment

Because the video camera 1 will be a parent device, the video camera 1sequentially performs the processing of step S1401, step S1402, and stepS1403 shown in FIG. 6 in the initial processing, establishing the deviceidentification information of the video camera 1 as C1 by the processingof step S1403, causing the identification information display device 5to display C1, and starting up the main processing at step S1405.Continuing, the video camera 1 executes the main processing and, by theprocessing at step S1508 (step S1601 to step S1610) detects the display2, and establishes the device identification information of the detecteddisplay 2 as D1. The video camera 1 also transmits the deviceidentification information and the communication status information tothe display 2.

The display 2 receives the device identification information and thecommunication status information that have been transmitted by the videocamera 1 executing the processing of step S1610. Then, the display 2causes display of the received device identification information D1 onthe identification information display device 7, and causes the receivedcommunication status information “C1→” to be displayed on thecommunication status display device 6. When this occurs, the videocamera 1 repeatedly executes the processing of step S1507, step S1508,step S1510, and step S1511.

When the video camera 3 power supply is turned on, the video camera 1detects the startup of the video camera 3 by the processing of stepS1508, and establishes the device identification information of thedetected video camera 3 as C2. The video camera 1 then transmits thedevice identification information and the communication statusinformation to the video camera 3 and the display 2. The video camera 3and the display 2 receive the device identification information and thecommunication status information that have been transmitted by executionof the processing of step S1610 by the video camera 1. Then, the videocamera 3 causes the display of the received device identificationinformation C2 on the identification information display device 8. Thedisplay 2 causes the display of the received device identificationinformation D1 on the identification information display device 7, andthe received communication status information “C1→” on the communicationstatus display device 6.

Finally, when the display 4 power supply is turned on, the video camera1 detects the display 4 by the processing of step S1508, and establishesthe device identification information of the detected display 4 as D2.The video camera 1 also transmits the device identification informationand the communication status information to the displays 2 and 4 and tothe video camera 3.

The displays 2 and 4 and the video camera 3 received the deviceidentification information and the communication status information thathave been transmitted by the video camera 1 executing the processing ofstep S1610. The display 4 causes the display of the received deviceidentification information D2 on the identification information displaydevice 10, and causes the display of the received communication statusinformation “C2→” on the communication status display device 9. Thevideo camera 3 causes the display of the received device identificationinformation C2 on the identification information display device 8. Thedisplay 2 causes the display of the device identification information D1on the identification information display device 7, and causes thedisplay of the received communication status information “C1→” on thecommunication status display device 6. At the point in time at which thevideo camera 1 or 3 being communicated with stops operating, the controlunits 20 of the display 2, 4 switch the right-direction arrow includedin the communication status information to blank.

Specific Example 2 of First Preferred Embodiment

The power supply of the video camera 1 is off, and the power supplies ofthe video cameras 3 and the displays 2 and 4 are sequentially turned on.As a result, although the description of the detailed operation will beomitted, the video camera 3 becomes a parent device. Also, image data istransmitted and received between the video camera 3 and the display 4.The device identification information displayed by the identificationinformation display device 8 mounted on the video camera 3 is C1. Thedevice identification information displayed by the device informationdisplay device 7 that is mounted on the display 7 is D1. The deviceidentification information displayed by the identification informationdisplay device 10 that is mounted on the display 4 is D2.

In this condition, when the video camera 1 power supply is turned on, inthe initial processing, the video camera 1 sequentially performs theprocessing of step S1401, S1402 and then step S1404, setting the localdevice to be a child device. When this is done, the video camera 3,which is a parent device, executes the main processing, detects thevideo camera 1 with the processing of step S1508, and establishes thedevice identification information of the detected video camera 1 as C2.The video camera 3 transmits the device identification information andthe communication status information to the video camera 1 and thedisplays 2 and 4.

The video camera 1 and the displays 2 and 4 receive the deviceidentification information and the communication status informationtransmitted by the execution by the video camera 3 of the processing ofstep S1610. The video camera 1 then causes display of the receiveddevice identification information C2 on the identification informationdisplay device 5. The display 2 causes display of the received deviceidentification information D1 on the identification information displaydevice 7, and causes display of the received communication statusinformation “C2→” on the communication status display device 6. Also,the display 4 causes display of the received device identificationinformation D2 on the identification information display device 10 andcauses display of the received communication status information “C1→” onthe communication status display device 9.

As described above, according to the first preferred embodiment, thevideo cameras 1 and 3 and the displays 2 and 4 cause display of deviceidentification information that uniquely displays each of the devicesthemselves on the displays 5, 7, 8, and 10. Also, the displays 2 and 4cause display on the communication information display devices 6 and 9of communication status information indicating the device identificationinformation and communication information of the device with which eachthemselves are communicating. By doing this, because the deviceidentification information and the communication status information aredisplayed in visual form, it is easy to grasp the operating status ofand the connection relationship between each device.

Also, although the first preferred embodiment has been described usingan example in which the device identification information is establishedusing the model name and the sequence of setting the deviceidentification information, this is not a restriction. For example, themethod of establishing the device identification information may be thatof using name of the manufacturer of a device, the manufacturing serialnumber of a device, or an abbreviated name of a device. As a specificexample, instead of a number assigned in the sequence of establishingthe device identification information, the lowest-order one digits ofthe manufacturing serial number of a device is used and, if there isduplication with other devices, the minimum number of digits are usedthat have not been used. Whereas in the case of assigning a number inthe sequence of establishing the device identification information, thedevice identification information varies, depending upon the sequence inwhich devices are turned on, if the lowest-order digit of themanufacturing serial number of the device is used, the deviceidentification information is semi-fixed, and the effect of animprovement in recognizability can also be expected. In this manner,while there are various methods of establishing the deviceidentification information, regardless of the method used the deviceidentification information is established so that devices within thecommunication system 100 are not assigned the same device identificationinformation.

Second Preferred Embodiment

Next, the second preferred embodiment of the present invention will bedescribed, with references being made to the drawings. FIG. 9 is asimplified drawing illustrating the constitution of a wirelesscommunication system in accordance with the second preferred embodimentof the present invention. In the illustrated example, a wirelesscommunication system 200 is constituted by two video cameras 21 and 23that have the function of wirelessly transmitting captured image data,two displays 22 and 24 that receive and display the image datatransmitted from the video cameras 21 and 23, and one controller 31(connection switching device) that controls the video cameras 21 and 23and the displays 22 and 24.

The video cameras 21 and 23 are constituted in the same manner as thevideo cameras 1 and 3 in the first preferred embodiment. The displays 22and 24 are constituted in the same manner as the displays 2 and 4 in thefirst preferred embodiment. Whereas, in the first preferred embodiment,the combinations of the video cameras 1 and 3 and the displays 2 and 4that communicate are pre-established and fixed, in the second preferredembodiment, the combinations of the video cameras 21 and 23 and thedisplays 22 and 24 that communicate can be arbitrarily changes by theoperation of the controller 31.

An identification information display device 25 is mounted on the videocamera 21, and an identification information display device 28 ismounted on the video camera 23. A communication status display device 26and an identification information display device 27 are mounted on thedisplay 22. A communication status display device 29 and anidentification information display device 30 are mounted to the display24. The identification information display devices 25, 27, 28, and 30and the communication status display devices 26 and 29 are similar tothe various parts of the first preferred embodiment. The secondpreferred embodiment differs from the first preferred embodiment in thatthe content displayed by the identification information display devices25, 27, 28, and 30 and the communication status display devices 26 and29 is set by the controller 31.

In the illustrated example, the identification information displaydevice 25 displays the device identification information C1 of the videocamera 21. The identification information display device 28 displays thedevice identification information C2 of the video camera 23. Theidentification information display device 27 displays the deviceidentification information D1 of the display 22. The identificationinformation display device 30 displays the device identificationinformation D2 of the display 24. The communication status displaydevice 26 displays C1, which is the device identification information ofthe communication destination video camera 21 of the display 22, and aright-direction arrow, which is information indicating thatcommunication with the communication destination video camera 21 is inprogress. The communication status display device 29 displays C2, whichis the device identification information of the communicationdestination video camera 23 of the display 24, and a right-directionarrow, which is information indicating that communication with thecommunication destination video camera 23 is in progress.

As described above, because the identification information displaydevices 25, 27, 28, and 30 display the device identification informationthat uniquely identifies their own devices, and the communication statusdisplay devices 26 and 29 display the communication status informationindicating the communication destinations and communication status ofthe displays 22 and 24, a user can easily verify in a visual manner thecombinations of video cameras 21 and 23 and the displays 22 and 24,which perform communication.

Next, the constitution of the controller 31 will be described. FIG. 10is a block diagram illustrating the constitution of the controller 31 inaccordance with the second preferred embodiment of the presentinvention. In the illustrated example, the controller 31 has anoperation instruction unit 32, a control unit 33, a display processingunit 34, a display unit 35, a wireless communication unit 36, an antenna37, and a storage unit 38.

The operation instruction unit 32 is operated by the user and acceptsinput of an instruction from the user. The content of an instruction,the input of which is accepted by the operation instruction unit 32, ispassed to the control unit 33. The control unit 33 controls variousparts of the controller 31 so that operation is performed in accordancewith the passed instruction content. Also, depending upon theinstruction content, the input of which is accepted by the operationinstruction unit 32, the control unit 33 generates control data. Thegenerated control data is then passed to the wireless communication unit36 and transmitted via the antenna 37 to the desired video camera 21, 23or display 22, 24. The storage unit 38 stores information necessary forprocessing by the various parts of the controller 31.

Next, an identification information display screen displayed on thedisplay unit 35 of the controller 31 will be described. FIG. 11 is asimplified drawing illustrating the identification information displayscreen in accordance with the second preferred embodiment of the presentinvention. The identification information display screen is a screendisplayed by the display unit 35 of the controller 31, this being ascreen that displays a listing of the device identification informationof the video cameras 21 and 23, and the displays 22 and 24 included inthe communication system 200. In the illustrated example, C1 and C2 aredisplayed as the device identification information of the video cameras21 and 23, and D1 and D2 are displayed as the device identificationinformation of the displays 22 and 24. By a user instruction, thecontroller 31 can change the content of the device identificationinformation.

Next, a connection information display screen displayed by the displayunit 35 of the controller 31 will be described. FIG. 12A and FIG. 12Bare simplified drawings illustrating connection information displayscreens in accordance with the second preferred embodiment of thepresent invention. The connection information display screen is a screenthat is displayed by the display unit 35 of the controller 31, thisscreen illustrating the combinations of connections between the videocameras 21 and 23 and the displays 22 and 24 included in thecommunication system 200.

The example shown in FIG. 12A indicates that the video camera 21 havingthe device identification information of C1 and the display 22 havingthe device identification information of D1 are communicating. It alsoindicates that the video camera 23 having the device identificationinformation of C2 and the display 24 having the device identificationinformation of D2 are communicating. In this condition, the user inputsto the operation instruction unit 32 of the control unit 31 aninstruction to make the communicating combination the combination of thevideo camera 21 having the device identification information of C1 andthe display 24 having the device identification information of D2, andthe combination of the video camera 23 having the device identificationinformation of C2 and the display 22 having the device identificationinformation of D1. If control by the controller 31 then changes thecombinations of the video cameras 21 and 23 and the displays 22 and 24that communicate, the connection information display screen displayed bythe display unit 35 of the controller 31 becomes the screen shown inFIG. 12B. The example shown in FIG. 12B indicates that the video camera21 having the device identification information of C1 and the display 24having the device identification information of D2 are communicating. Italso indicates that the video camera 23 having the device identificationinformation of C2 and the display 22 having the device identificationinformation of D1 are communicating.

Next, the processing protocol for controller communication processing bythe controller 31 will be described. FIG. 13 is a flowchart illustratingthe processing protocol for controller communication processing by thecontroller 31 in accordance with the second preferred embodiment of thepresent invention. The controller communication processing is executeduntil the controller 31 power supply is turned off.

(Step S2201)

The control unit 33 of the controller 31 starts the controllercommunication processing. After that, processing proceeds to step S2202.

(Step S2202)

The control unit 33 reads in the identification information controltable and the communication status control table that had been caused tobe stored in the storage unit 38 immediately before the last time thepower supply of the controller 31 was turned off. Based on theinformation stored in the read-in identification information controltable and communication status control table, the control unit 33 causesthe display processing unit 34 to perform display processing, and causesthe display unit 35 to display the connection information displayscreen. After that, processing proceeds to step S2203.

(Step S2203)

The control unit 33 executes terminal exploring processing and tableupdating processing. After that, processing proceeds to step S2204. Theterminal exploring processing and the table updating processing will bedescribed later.

(Step S2204)

The control unit 33 judges whether or not the operation instruction unit32 has accepted an input of a connection change. If the control unit 33judges that the operation instruction unit 32 has accepted the input ofa connection change, processing proceeds to step S2205, and if thecontrol unit 33 judges that the operation instruction unit 32 hasaccepted the input of a connection change, processing proceeds to stepS2206.

(Step S2205)

The control unit 33, based on the input of a connection change acceptedby the operation instruction unit 32, updates the identificationinformation control table and the communication status control tablestored in the storage unit 38. The control unit 33 updates the displaycontent of the connection information display screen displayed on thedisplay unit 35 based on the information stored in the identificationinformation control table and the communication status control tableafter updating. After that, processing proceeds to step S2206.

(Step 2206)

The control unit 33 judges whether or not the wireless communicationunit 36 has received an information updating request signal transmittedfrom another device. If the control unit 33 judges that the wirelesscommunication unit 36 has received an information updating requestsignal, processing proceeds to step S2207, and if the control unit 33judges that the operation instruction unit 32 has not accepted input ofa connection change, processing returns to step S2203.

(Step S2207)

The control unit 33 reads out the device identification information andthe communication status information of device that is the transmissionsource of the information updating request signal, which is stored inthe identification information control table and the communicationstatus control table stored in the storage unit 38. The control unit 33then judges whether or not the read-out device identificationinformation and communication status information have been furtherupdated after the last transmission to the device that is thetransmission source of the information updating request signal. Thecontrol unit 33 then controls the communication unit 36 and transmits tothe device that is the source of the transmission of the informationupdating request signal the result of the judgment of whether or notthere has been an updating. If the judgment is made that the deviceidentification information and the communication status information hadbeen updated to the device that is the transmission source ofinformation updating request signal since the last transmission, thecontrol unit 33 controls the communication unit 36 to transmit theread-out device identification information and communication statusinformation to the device that is the source of the information updatingrequest signal. After that, processing returns to step S2203.

Next, the processing protocol of the terminal exploring processing andthe table updating processing of the controller 31 will be described.FIG. 14 is a flowchart illustrating the processing protocol of theterminal exploring processing and the table updating processing by thecontroller 31 in accordance with the second preferred embodiment of thepresent invention. The point of difference with respect to the terminalexploring processing and table updating processing in the firstpreferred embodiment is that the terminal exploring processing and tableupdating processing in the second preferred embodiment does not performthe processing of step S1610 of FIG. 6.

Because the processing of step S2301 to step S2307 is processing that isthe same as the processing of step S1601 to step S1607 in the firstpreferred embodiment, the description thereof will be omitted.

(Step S2308)

The control unit 33 compares the ID numbers included in the responsesignals received at step S2303 with the ID numbers stored in theidentification information control table. The control unit 33 thendetects as a non-responding ID number an ID number that is not includedin the response signals, is stored in the identification informationcontrol table, and also has a power supply status flag that is on. Ifthe control unit 33 detects a non-responding ID number, processingproceeds to step S2309, and if the control unit 33 does not detect anon-responding ID number, the terminal exploring processing and tableupdating processing are ended, and processing proceeds to step S2204 ofthe controller communication processing.

(Step S2309)

The control unit 33, of the power supply flags stored in the informationcontrol table, sets to off the power supply flag of the ID numberdetected as a non-responding ID number at step S2308 (performs powersupply flag off-setting processing). After that, the terminal exploringprocessing and table updating processing are ended, and processingproceeds to step S2204 of the controller communication processing.

By executing the above-described controller communication processing,and the terminal exploring processing and table updating processing, thecontroller 31 can update the device identification information andcommunication status information of each device included in thecommunication system 100.

Next, the processing protocol of the video camera processing of thevideo cameras 21 and 23 will be described. FIG. 15 is a flowchartillustrating the processing protocol of the video cameras 21 and 23 inaccordance with the second preferred embodiment of the presentinvention. The video camera processing is executed in the video cameras21 and 23 until the power supplies of each of the devices is turned off.

(Step S2001)

The control unit 15 of the video cameras 21 and 23 starts the videocamera processing when its power supply is turned on. After that,processing proceeds to step

(Step S2002)

The control unit 15 reads in the device identification information andthe communication status information that had been caused to be storedin the storage unit 51 immediately before the last time the power supplyof the local device was turned off. After that, processing proceeds tostep S2003.

(Step S2003)

The control unit 15 controls the wireless communication unit 13 so as totransmit an information updating request signal to the controller 31. Asdescribed above, having received an information updating request signal,the controller 31 transmits to the video camera 21, 23 that hastransmitted the information updating request signal the result of thejudgment of whether or not updating had been done after the last timethe device identification information and the communication statusinformation have been transmitted. The wireless communication unit 13receives the judgment result via the antenna 14. The control unit 15,based on the judgment result received by the wireless communication unit13, judges whether or not the device identification information and thecommunication status information had been updated. If the control unit15 judges that the device identification information and thecommunication status information had been updated, processing proceedsto step S2004, and if the control unit 15 judges that updating had notbeen done, processing proceeds to step S2005. After transmission of theinformation updating request signal, if the wireless communication unit13 did not receive the judgment result for the reason that thecontroller 31 does not operate, processing proceeds to step S2005.

(Step S2004)

As described above, if the controller 31 judges that updating has beendone after the last time the device identification information and thecommunication status information were transmitted to the device that isthe transmission source of the information updating request signal, thedevice identification information and the communication statusinformation after updating are transmitted. The wireless communicationunit 13 receives the updated device identification information andcommunication status information via the antenna 14. The control unit 15updates the device identification information and the communicationstatus information stored in the storage unit 51 to the deviceidentification information and the communication status informationreceived by the wireless communication unit 13. The control unit 15 alsocauses the identification information display device 25, 28 mounted toits own device to display the device identification information of itsown device stored in the storage unit 51. After that, processingproceeds to step S2005.

(Step S2005)

The control unit 15, based on the communication status informationstored in the storage unit 51, judges whether or not the display 22, 24that is the communication destination of its own device is operating. Ifthe control unit 15 judges that the display 22, 24 that is its device'scommunication destination is operating, processing proceeds to stepS2006, and if the control unit 15 judges that the display 22, 24 that isthe communication destination of its own device is not operating,processing proceeds to step S2007.

(Step S2006)

The control unit 15 controls the wireless communication unit 13 so thatthe image data for one screen that has been captured by the imaging unit11 and image-processed by the image processing unit 12 is transmitted tothe display unit 22, 24. After that, processing returns to step S2003.

(Step 2007)

After a certain amount of waiting time, the control unit 15 returns tothe processing of step S2003.

By executing the above-described video camera processing, even if therehad been updating of the device identification information and thecommunication status information of the local device, the video camera21, 23 can receive the device identification information and thecommunication status information of the local device from the controller31. Then, the video camera 21, 23 can cause the updated deviceidentification information to be displayed on the identificationinformation display device 25, 28 mounted to its device. Also, based onthe communication status information, the video camera 21, 23 canidentify the display 22, 24 that is the communication destination of itsown device and, if the display 22, 24 that is its device's communicationdestination is operating, it can transmit the captured image data to thedisplay 22, 24.

Next, the processing protocol of the display processing of the displays22 and 24 will be described. FIG. 16 is a flowchart illustrating theprocessing protocol of the displays 22 and 24 in accordance with thesecond preferred embodiment of the present invention. The displayprocessing is executed in the displays 22 and 24 until the power supplyof each device is turned off.

(Step S2101)

The control unit 20 of the display 22, 24 starts the display processingwhen the power supply of its device is turned on. After that, processingproceeds to step S2102.

(Step S2102)

The control unit 20 reads in the device identification information andthe communication status information stored in the storage unit 52immediately before the last time the power supply of the local devicewas turned off. After that, processing proceeds to step S2103.

(Step S2103)

The control unit 20 controls the wireless communication unit 17 totransmit an information updating request signal to the controller 31. Asdescribed above, upon receiving an information updating request signal,the controller 31 transmits to the display 22, 24 that has transmittedan information updating request signal the result of the judgment ofwhether or not updating had been done after the last time the deviceidentification information and the communication status information weretransmitted. The wireless communication unit 17 receives the judgmentresult via the antenna 16. The control unit 20, based on the result ofthe judgment received by the wireless communication unit 17, judgeswhether or not the device identification information and thecommunication status information had been updated. If the control unit20 judges that the device identification information and thecommunication status information had been updated, processing proceedsto step S2104, and if the control unit 20 judges that updating had notbeen done, processing proceeds to step S2105. After transmission of theinformation updating request signal, if the wireless communication unit17 did not receive the judgment result for the reason that thecontroller 31 does not operate, processing proceeds to step S2105.

(Step S2104)

As described above, if the controller 31 judges that updating had beendone after the last time the device identification information and thecommunication status information were transmitted to the device that isthe transmission source of the information updating request signal, thedevice identification information and the communication statusinformation after updating are transmitted. The wireless communicationunit 17 receives the updated device identification information andcommunication status information via the antenna 16. The control unit 20updates the device identification information and the communicationstatus information stored in the storage unit 52 to the deviceidentification information and the communication status informationreceived by the wireless communication unit 17. The control unit 20 alsocauses the identification information display device 27, 30 mounted toits own device to display the device identification information of itsown device stored in the storage unit 52. The control unit 20 alsocauses the communication status display device 26, 29 mounted to its owndevice to display the communication status information stored in thestorage unit 52. After that, processing proceeds to step S2105.

(Step S2105)

The control unit 20, based on the communication status informationstored in the storage unit 52, judges whether or not the video camera21, 23 that is the communication destination of its own device isoperating. If the control unit 20 judges that the video camera 21, 23that is its device's communication destination is operating, processingproceeds to step S2016, and if the control unit 20 judges that the videocamera 21, 23 that is the communication destination of its own device isnot operating, processing proceeds to step S2107.

(Step S2106)

The control unit 20 controls the wireless communication unit 13 so as toreceive the image data for one screen transmitted from the communicationdestination video camera 21, 23. The control unit 20 also causes theimage processing unit 18 to image-process the received image data andcauses display on the image display unit 19.

(Step S2107)

After a certain amount of waiting time, the control unit 20 returns tothe processing of step S2103.

By executing the above-described display processing, even if there hadbeen updating of the device identification information and thecommunication status information of the local device, the display 22, 24can receive the device identification information and the communicationstatus information of the local device from the controller 31. Then, thedisplay 22, 24 can cause display of updated device identificationinformation on the identification information display device 25, 28mounted to its device, and cause display of the updated communicationstatus information on the communication status display 26, 29. Thedisplay 22, 24 can cause display, on the image display unit 19, of theimage data transmitted from the video camera 21, 23 that is itscommunication destination.

Next, the specific operation of the communication system 200 of thesecond preferred embodiment will be described.

Specific Example 1 of Second Preferred Embodiment

The case in which, in the communication system 200, the power suppliesof the video camera 21 and the display 22 are on, the power supplies ofthe video camera 23, the display 24, and controller 31 are off, and, inthe condition in which the video camera 21 and the display 22 arecommunicating, the power supply of the controller 31 is turned on.

Specific Example 2 of Second Preferred Embodiment

The case in which, in the condition in which the communication system200, the power supplies of the controller 31, the video cameras 21 and23, and the displays 22 and 24 are on, the video camera 21 and thedisplay 22 are communicating, and the video camera 23 and the display 24are communication, the user inputs a connection change to the operationinstruction unit 32 of the controller 31, the communication destinationof the video camera 21 being switched to the display 24 and thecommunication destination of the video camera 23 being switched to thedisplay 22.

The above-noted two specific examples will be described.

Specific Example 1 of Second Preferred Embodiment Video Camera 21Processing

Immediately after its own device power supply is turned on, the videocamera 21 sequentially performs the processing of step S2001 and thenstep S2002 shown in FIG. 15, and reads in the device identificationinformation and the communication status information that had beenstored in the storage unit 51 immediately before the last time the powersupply of its device was turned off. Next, in the processing of stepS2003, an information updating request signal is transmitted to thecontroller 31, and a query is made as to whether or not there isupdating of the device identification information and the communicationstatus information. If there is updating of the device identificationinformation and the communication status information, by the processingof step S2004 the updated device identification information and thecommunication status information transmitted from the controller 31 arereceived, the device identification information and the communicationstatus information stored in the storage unit 51 being updated to thereceived device identification information and communication statusinformation, and processing proceeding to step S2005. If, in theprocessing of step S2003, there had been no updating of the deviceidentification information and the communication status information, orif the controller 31 is not operating and there is no response,processing proceeds to step S2005.

In the processing of step S2005, because the display 22 is alreadyoperating, processing proceeds to step S2006. In the processing of stepS2006, the video camera 21 transmits one frame of image data to thedisplay 22. Thereafter, the video camera 21 repeats in sequenceexecution of the processing of step S2003, step S2005, and step S2006.

(Display 22 Processing)

Immediately after its own device power supply is turned on, the display22 sequentially performs the processing of step S2101 and then stepS2102 shown in FIG. 16, and reads in the device identificationinformation and the communication status information that had beenstored in the storage unit 52 immediately before the last time the powersupply of its device was turned off. Next, in the processing of stepS2103, an information updating request signal is transmitted to thecontroller 31, and a query is made as to whether or not there isupdating of the device identification information and the communicationstatus information. If there is updating of the device identificationinformation and the communication status information, by the processingof step S2104, the updated device identification information and thecommunication status information transmitted from the controller 31 arereceived, the device identification information and the communicationstatus information stored in the storage unit 52 being updated to thereceived device identification information and communication statusinformation, and processing proceeding to step S2105. If, in theprocessing of step S2103, there had been no updating of the deviceidentification information and the communication status information, orif the controller 31 is not operating and there was no response,processing proceeds to step S2105.

In the processing of step S2105, because the video camera 21 is alreadyoperating, processing proceeds to step S2106. In the processing of stepS2106, the display 22 receives and causes display on the image displayunit 19 of one frame of image data from the video camera 21. Therefore,the display 22 repeats in sequence execution of the processing of stepS2103, step S2105, and step S2106.

(Controller 31 Processing)

Immediately after the power supply is applied, the controller 31sequentially performs the processing of step S2201 and then step S2202shown in FIG. 13, and reads in the identification information controltable and the communication status control table that had been stored inthe storage unit 38 immediately before the last time the power supplywas turned off. Next, in the processing of step S2203, the video camera21 and the display 22 are explored, the device identificationinformation of the video camera 21 being established as C1, the deviceidentification information of the display 22 being established as D1,and the identification information control table and the communicationstatus control table stored in the storage unit 38 being updated. Atthis point in time, the device identification information of the videocamera 21 and the display 22 are established, and the display content ofthe identification information display screen shown in FIG. 11 isestablished.

In the processing of step S2204, the control unit 33 of the controller31 judges whether or not the operation instruction unit 32 has acceptedinput of a connection change. In this specific example, because theoperation instruction unit 32 has not accepted input of a connectionchange, processing proceeds to step S2206. In the processing of stepS2206, a judgment is made of whether or not an information updatingrequest signal has been received from the video camera 21 and thedisplay 22. If an information updating request signal has been received,processing proceeds to step S2207, and if an information updatingrequest signal has not been received, processing proceeds to step S2203.

In the processing of step S2207, controller 31 transmits to the videocamera 21 and the display 22 that are the transmission sources of theinformation updating signal the result of a judgment of whether or notthe device identification information and the communication statusinformation were updated after the last time the device identificationinformation and the communication status information were transmitted.If the device identification information and the communication statusinformation has been updated after the last time the deviceidentification information and the communication status information weretransmitted, the controller 31 transmits the updated deviceidentification information and communication status information to thevideo camera 21 and the display 22. At this point in time, the videocamera 21 and the display 22 cause the display of the received deviceidentification information on the identification information displaydevice 25, 27. The display 22 causes display of the received deviceidentification information on the communication status display device26. Thereafter, the controller 31 repeats in sequence execution of theprocessing of step S2203, step S2204, step S2206, and step S2207.

Specific Example 2 of Second Preferred Embodiment Video Camera 21, 23Processing

The processing of video cameras 21 and 23 is the same processing as thatof the video camera 21 in Specific Example 1.

(Display 22, 24 Processing)

The processing of displays 22 and 24 is the same processing as that ofthe display 22 in Specific Example 1.

(Controller 31 Processing)

Immediately after the power supply is applied, the controller 31sequentially performs the processing of step S2201 and then step S2202shown in FIG. 13, and reads in the identification information controltable and the communication status control table that had been stored inthe storage unit 38 immediately before the last time the power supplywas turned off. Next, in the processing of S2203, the video cameras 21and 23 and the displays 22 and 24 are explored, the deviceidentification information of the video camera 21 being established asC1, the device identification information of the video camera 23 beingestablished as C2, the device identification information of the display22 being established as D1, the device identification information of thedisplay 24 being established as D2, and the identification informationcontrol table and the communication status control table stored in thestorage unit 38 being updated. At this point in time, the deviceidentification information of the video cameras 21 and 23 and thedisplays 22 and 24 are established, and the display content of theidentification information display screen shown in FIG. 11 isestablished.

In the processing of step S2204, the control unit 33 of the controller31 judges whether or not the operation instruction unit 32 has acceptedinput of a connection change. In this specific example, because the userinputs a connection change to the operation instruction unit 32 of thecontroller 31, the communication destination of the video camera 21being switched to the display 24 and the communication destination ofthe video camera 23 being switched to the display 22, processingproceeds to step S2205. In the processing of step S2205, the controlunit 33 of the controller 31, based on the input of the connectionchange received by the operation instruction unit 32, updates theidentification information control table and the communication statuscontrol table stored in the storage unit 38. At this point in time, theconnection relationship is established so that the communicationdestination of the video camera 21 (device identification informationC1) is the display 24 (device identification information D2), and thecommunication destination of the video camera 23 (device identificationinformation C2) is the display 22 (device identification informationD1), the content displayed on the connection information display screenbeing as shown in FIG. 12(2).

In the processing of step S2206, a judgment is made of whether or not aninformation updating request signal has been received from the videocamera 21, 23 and display 22, 24. If an information updating requestsignal had been received, processing proceeds to step S2207, and if aninformation updating request signal had not been received, processingreturns to step S2203.

In the processing of step S2207, the controller 31 transmits to thevideo camera 21, and 23 and display 22 and 24 that are the transmissionsources of the information updating signal the result of a judgment ofwhether or not the device identification information and thecommunication status information has been updated after the last timethe device identification information and the communication statusinformation were transmitted. Because the device identificationinformation and the communication status information had not beenupdated after the last time the device identification information andthe communication status information were transmitted, the controller 31transmits the updated device identification information andcommunication status information to the video camera 21, 23 and thedisplay 22, 24. At this point in time, the video camera 21, 23 and thedisplay 22, 24 cause display of the received device identificationinformation on the identification information display devices 25, 27,28, and 30. The display 22, 24 cause display of the receivedcommunication status information on the communication status displaydevices 26 and 29. Thereafter, the controller 31 repeats in sequenceexecution of the processing step S2203, step S2204, step S2206, and stepS2207.

As described above, according to the second preferred embodiment, thevideo camera 21, 23 and the display 22, 24 cause display of deviceidentification information that uniquely identifies their devices on theidentification information display devices 25, 27, 28, and 30. Thedisplay 22, 24 cause display of communication status information thatindicates device identification information and communicationinformation of the communication destination devices of their devices onthe communication status display devices 26 and 29. By doing this,because the device identification information and the communicationstatus information are displayed in a visual manner, it is easy to graspthe operating status and connection relationship of each device.

Also, according to the second preferred embodiment, because thecommunication system 200 includes the controller 31, the flow of imagedata between the video cameras 21 and 23 and the displays 22 and 24 canbe switched. By doing this, the communication system 200 has increasedflexibility and convenience as a wireless communication system. Also,because the device identification information that uniquely identifiesthe video cameras 21 and 23 and the displays 22 and 24 included in thecommunication system 200 is displayed on the display unit 35 of thecontroller 31, the user can quickly view the devices that are actuallyincluded in the communication system 200.

Also, the second preferred embodiment has been described for an examplein which the video cameras 21 and 23, the displays 22 and 24 areconnected with the identification information display devices 25, 27,28, and 30. Although this is to enhance the recognition of the deviceidentification information of each of the devices, depending upon thecondition of the communication system 200, the identificationinformation display devices 25, 27, 28, and 30 may be connected to onlya part of the devices, and the device identification information of eachdevice may be made to be displayed on the display unit 35 of thecontroller 31.

For example, a communication system may be constituted so that theidentification information display devices 28 and 30 connected to thevideo camera 23 and the display 24 in the communication system 200 inFIG. 9 are eliminated, the device identification information of thevideo camera 23 and the display 24 being caused to be displayed on thedisplay unit 35 of the controller 31, so that the device identificationinformation of each device is verified on the display unit 25 of thecontroller 31.

Also, in the communication system 200 shown in FIG. 9, because it is notnecessary to display identification information, such as in the case inwhich there exist video cameras and displays that are not illustratedand operate at all times with fixed connections, the identificationinformation display devices need not be connected to these video camerasand displays.

Although the above has been a detailed description of the first andsecond preferred embodiments of the present invention, with referencesmade to the drawings, the specific constitution is not restricted tothese preferred embodiments, and encompasses design changes and the likewithin the scope of the spirit of the present invention.

The present invention can be applied to a display device, a receivingdevice, a transmitting device, and a wireless communication system, andfacilitates an understanding of the wireless communication connectionrelationship.

According to the display device, the transmitting terminal, and thereceiving terminal in accordance with a preferred embodiment of thepresent invention, an acquisition unit acquires transmitting terminalidentification information that is identification information of atransmitting terminal transmitting image data by wireless communication,and receiving terminal identification information that is identificationinformation of a receiving terminal receiving the image data by wirelesscommunication. Also, an information display unit displays thetransmitting terminal identification information and the receivingterminal identification information. By doing this, because thetransmitting terminal identification information of the transmittingterminal that transmits image data and the receiving terminalidentification information of the receiving terminal that receives imagedata are displayed on the information display unit, it is easy tounderstand the wireless communication connection relationship.

According to the wireless communication system in accordance with apreferred embodiment of the present invention, the plurality ofidentification information display devices visually display theidentification information established for each individual communicationdevice. A communication status display device displays the flow of imagedata between the communication devices. Also, the identificationinformation is uniquely established at the time the communication devicejoins the network. By doing this, the identification information ofcommunication devices that transmit and receive image data is displayedon the identification information display device, and the flow of imagedata between communication devices is displayed on the communicationstatus display device, thereby facilitating an understanding of thewireless communication connection relationship.

What is claimed is:
 1. A wireless communication system, in which aterminal that wirelessly transmits image data is referred to as atransmitting terminal, a terminal that wirelessly receives image data isreferred to as a receiving terminal, and a device that instructs toswitch a wireless communication connection between the transmittingterminal and the receiving terminal is referred to as a connectionswitching device, the wireless communication system having a pluralityof the transmitting terminals, a plurality of the receiving terminals,and at least one of the connection switching device, the wirelesscommunication system comprising: a first display device connected bycable to the transmitting terminal; and a second display deviceconnected by cable to the receiving terminal, wherein the connectionswitching device includes: a control unit configured to establishtransmitting terminal identification information that is identificationinformation of the transmitting terminal and receiving terminalidentification information that is identification information of thereceiving terminal; a wireless communication unit configured towirelessly transmit the established transmitting terminal identificationinformation to the transmitting terminal and wirelessly transmit theestablished receiving terminal identification information to thereceiving terminal; and a display unit configured to display thetransmitting terminal identification information of the transmittingterminal that is currently communicating with the receiving terminal,the receiving terminal identification information of the receivingterminal that is currently communicating with the transmitting terminal,and information indicating which transmitting terminal the image data iswirelessly transmitted from and which receiving terminal the image datais wirelessly transmitted to, the wireless communication unit of theconnection switching device performs at least one of a wirelesstransmission of the receiving terminal identification information of thereceiving terminal, which is currently communicating with thetransmitting terminal, to the transmitting terminal, and a wirelesstransmission of the transmitting terminal identification information ofthe transmitting terminal, which is currently communicating with thereceiving terminal, to the receiving terminal, the first display devicedisplays the receiving terminal identification information that iswirelessly transmitted from the wireless communication unit of theconnection switching device and wirelessly received by the transmittingterminal, and the second display device displays the transmittingterminal identification information that is wirelessly transmitted fromthe wireless communication unit of the connection switching device andwirelessly received by the receiving terminal.
 2. The wirelesscommunication system according to claim 1, wherein the control unit ofthe connection switching device executes exploring processing in whichthe transmitting terminal and the receiving terminal are explored, andupdates the transmitting terminal identification information and thereceiving terminal identification information in accordance with aresult of the exploring processing, and the wireless communication unitof the connection switching device performs at least one of a wirelesstransmission of the updated transmitting terminal identificationinformation of the transmitting terminal to the transmitting terminaland a wireless transmission of the updated receiving terminalidentification information of the receiving terminal to the transmittingterminal or the receiving terminal.
 3. The wireless communication systemaccording to claim 1, wherein the control unit of the connectionswitching device updates information indicating which transmittingterminal the image data displayed on the display unit of the connectionswitching device is wirelessly transmitted from and which receivingterminal the image data displayed on the display unit is wirelesslytransmitted to.
 4. The wireless communication system according to claim1, wherein the transmitting terminal or the receiving terminalwirelessly transmits an information updating request signal forconfirming whether or not the transmitting terminal identificationinformation or the receiving terminal identification information hasbeen updated, to the connection switching device.
 5. A receivingterminal, in which a terminal that wirelessly transmits image data isreferred to as a transmitting terminal, a terminal that wirelesslyreceives image data is referred to as a receiving terminal, and a devicethat instructs to switch a wireless communication connection between thetransmitting terminal and the receiving terminal is referred to as aconnection switching device, the receiving terminal comprising: acontrol unit connected by cable to a display device; and a wirelesscommunication unit configured to receive transmitting terminalidentification information, which is identification information of thetransmitting terminal that is currently communicating with the receivingterminal, from the connection switching device, wherein the control unitcontrols the display device to display the transmitting terminalidentification information of the transmitting terminal that iscurrently communicating with the receiving terminal, and informationindicating which transmitting terminal the image data is wirelesslytransmitted from, which are wirelessly received.
 6. The receivingterminal according to claim 5, wherein the wireless communication unitwirelessly transmits an information updating request signal forconfirming whether or not the transmitting terminal identificationinformation or receiving terminal identification information that isidentification information of the receiving terminal has been updated,to the connection switching device.
 7. A transmitting terminal, in whicha terminal that wirelessly transmits image data is referred to as atransmitting terminal, a terminal that wirelessly receives image data isreferred to as a receiving terminal, and a device that instructs toswitch a wireless communication connection between the transmittingterminal and the receiving terminal is referred to as a connectionswitching device, the transmitting terminal comprising: a control unitconnected by cable to a display device; and a wireless communicationunit configured to receive receiving terminal identificationinformation, which is identification information of the receivingterminal that is currently communicating with the transmitting terminal,from the connection switching device, wherein the control unit controlsthe display device to display the receiving terminal identificationinformation of the receiving terminal that is currently communicatingwith the transmitting terminal, and information indicating that theimage data is wirelessly transmitted to which receiving terminal, whichare wirelessly received.
 8. The transmitting terminal according to claim7, wherein the wireless communication unit wirelessly transmits aninformation updating request signal for confirming whether or nottransmitting terminal identification information, which isidentification information of the transmitting terminal information, orthe receiving terminal identification information has been updated, tothe connection switching device.
 9. A wireless communication system, inwhich a terminal that wirelessly transmits image data is referred to asa transmitting terminal and a terminal that wirelessly receives imagedata is referred to as a receiving terminal, the wireless communicationsystem having a plurality of the transmitting terminals and a pluralityof the receiving terminals, the wireless communication systemcomprising: a first display device connected by cable to thetransmitting terminal; and a second display device connected by cable tothe receiving terminal, wherein a first transmitting terminal is one ofthe plurality of the transmitting terminals, and a second transmittingterminal is another of the plurality of the transmitting terminals, thefirst transmitting terminal includes: a control unit configured toestablish first transmitting terminal identification information that isidentification information of the first transmitting terminal, secondtransmitting terminal identification information that is identificationinformation of the second transmitting terminal, and receiving terminalidentification information that is identification information of thereceiving terminal; and a wireless communication unit configured toperform at least one of a wireless transmission of the establishedsecond transmitting terminal identification information and theestablished receiving terminal identification information of thereceiving terminal that is currently communicating with the secondtransmitting terminal, to the second transmitting terminal, and awireless transmission of the established receiving terminalidentification information and the transmitting terminal identificationinformation of one of the first transmitting terminal and the secondtransmitting terminal, which is currently communicating with thereceiving terminal, to the receiving terminal, and the first displaydevice connected by cable to the second transmitting terminal displaysthe receiving terminal identification information of the receivingterminal that is currently communicating with the second transmittingterminal, and information indicating which receiving terminal the imagedata is wirelessly transmitted to, which are wirelessly transmitted fromthe first transmitting terminal and wirelessly received by the secondtransmitting terminal, or the second display device displays, thetransmitting terminal identification information of one of the firsttransmitting terminal and the second transmitting terminal, which iscurrently communicating with the receiving terminal, and informationindicating which of the first transmitting terminal and the secondtransmitting terminal the image data is wirelessly transmitted from,which are wirelessly transmitted from the first transmitting terminaland wirelessly received by the second transmitting terminal.
 10. Thewireless communication system according to claim 9, wherein the controlunit of the first transmitting terminal executes exploring processing inwhich the transmitting terminal and the receiving terminal are explored,and updates the transmitting terminal identification information and thereceiving terminal identification information in accordance with aresult of the exploring processing, and the wireless communication unitof the first transmitting terminal wirelessly transmits the updatedtransmitting terminal identification information and the updatedreceiving terminal identification information to the second transmittingterminal and the receiving terminal.
 11. The wireless communicationsystem according to claim 9, wherein the transmitting terminal judgeswhether or not the first transmitting terminal exists, the transmittingterminal is set to be the first transmitting terminal when thetransmitting terminal judges that the first transmitting terminal doesnot exist, and the transmitting terminal is set to be the secondtransmitting terminal when the transmitting terminal judges that thefirst transmitting terminal exists.
 12. A receiving terminal, in which aterminal that wirelessly transmits image data is referred to as atransmitting terminal and a terminal that wirelessly receives image datais referred to as a receiving terminal, the receiving terminalcomprising: a control unit connected by cable to a display device; and awireless communication unit configured to wirelessly receivetransmitting terminal identification information that is identificationinformation of the transmitting terminal that is currently communicatingwith the receiving terminal, from the transmitting terminal, wherein thecontrol unit controls the display device to display the transmittingterminal identification information of the transmitting terminal that iscurrently communicating with the receiving terminal, and informationindicating which transmitting terminal the image data is wirelesslytransmitted from, which are wirelessly received.
 13. A transmittingterminal, in which a terminal that wirelessly transmits image data isreferred to as a transmitting terminal and a terminal that wirelesslyreceives image data is referred to as a receiving terminal, thetransmitting terminal comprising: a control unit connected by cable to adisplay device; and a wireless communication unit configured towirelessly receive receiving terminal identification information that isidentification information of the receiving terminal that is currentlycommunicating with the transmitting terminal, from another transmittingterminal, wherein the control unit controls the display device todisplay the receiving terminal identification information of thereceiving terminal that is currently communicating with the transmittingterminal, and information indicating which receiving terminal the imagedata is wirelessly transmitted to, which are wirelessly received.
 14. Awireless communication method, in which a terminal that wirelesslytransmits image data is referred to as a transmitting terminal and aterminal that wirelessly receives image data is referred to as areceiving terminal, the wireless communication method comprising: a stepof establishing the transmitting terminal identification information andthe receiving terminal identification information; a step of wirelesslytransmitting the established transmitting terminal identificationinformation to the transmitting terminal and wirelessly transmitting theestablished receiving terminal identification information to thereceiving terminal; a step of displaying the transmitting terminalidentification information of the transmitting terminal that iscurrently communicating with the receiving terminal, the receivingterminal identification information of the receiving terminal that iscurrently communicating with the transmitting terminal, and informationindicating which transmitting terminal the image data is wirelesslytransmitted from and which receiving terminal the image data iswirelessly transmitted to; a step of performing at least one of awireless transmission of the receiving terminal identificationinformation of the receiving terminal, which is currently communicatingwith the transmitting terminal, to the transmitting terminal, and awireless transmission of the transmitting terminal identificationinformation of the transmitting terminal, which is currentlycommunicating with the receiving terminal, to the receiving terminal;and a step of performing at least one of displaying the receivingterminal identification information of the receiving terminal that iswirelessly received by the transmitting terminal and the transmittingterminal identification information of the transmitting terminal that iswirelessly received by the receiving terminal.
 15. A wirelesscommunication method, in which a terminal that wirelessly transmitsimage data is referred to as a transmitting terminal and a terminal thatwirelessly receives image data is referred to as a receiving terminal,the wireless communication method comprising: a step of establishingfirst transmitting terminal identification information that isidentification information of a first transmitting terminal that is oneof a plurality of the transmitting terminals, second transmittingterminal identification information that is identification informationof a second transmitting terminal that is another of the plurality ofthe transmitting terminals, and the receiving terminal identificationinformation by the first transmitting terminal; a step of performing atleast one of a wireless transmission of the established secondtransmitting terminal identification information and the establishedreceiving terminal identification information of the receiving terminalthat is currently communicating with the second transmitting terminal,to the second transmitting terminal, and a wireless transmission of theestablished receiving terminal identification information and thetransmitting terminal identification information of one of the firsttransmitting terminal and the second transmitting terminal, which iscurrently communicating with the receiving terminal, to the receivingterminal; and a step of performing at least one of displaying thereceiving terminal identification information of the receiving terminal,which is currently communicating with the second transmitting terminal,and information indicating which receiving terminal the image data iswirelessly transmitted to, which are wirelessly transmitted from thefirst transmitting terminal and wirelessly received by the secondtransmitting terminal, and displaying the transmitting terminalidentification information of one of the first transmitting terminal andthe second transmitting terminal, which is currently communicating withthe receiving terminal, and information indicating which of the firsttransmitting terminal and the second transmitting terminal the imagedata is wirelessly transmitted from, which are wirelessly transmittedfrom the first transmitting terminal and wirelessly received by thesecond transmitting terminal.